build: move e2e dependencies into e2e/go.mod

Several packages are only used while running the e2e suite. These
packages are less important to update, as the they can not influence the
final executable that is part of the Ceph-CSI container-image.

By moving these dependencies out of the main Ceph-CSI go.mod, it is
easier to identify if a reported CVE affects Ceph-CSI, or only the
testing (like most of the Kubernetes CVEs).

Signed-off-by: Niels de Vos <ndevos@ibm.com>

e2e/vendor/k8s.io/client-go/features/envvar.go

@@ -0,0 +1,188 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package features
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"sync"
+	"sync/atomic"
+
+	"k8s.io/apimachinery/pkg/util/naming"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/klog/v2"
+)
+
+// internalPackages are packages that ignored when creating a name for featureGates. These packages are in the common
+// call chains, so they'd be unhelpful as names.
+var internalPackages = []string{"k8s.io/client-go/features/envvar.go"}
+
+var _ Gates = &envVarFeatureGates{}
+
+// newEnvVarFeatureGates creates a feature gate that allows for registration
+// of features and checking if the features are enabled.
+//
+// On the first call to Enabled, the effective state of all known features is loaded from
+// environment variables. The environment variable read for a given feature is formed by
+// concatenating the prefix "KUBE_FEATURE_" with the feature's name.
+//
+// For example, if you have a feature named "MyFeature"
+// setting an environmental variable "KUBE_FEATURE_MyFeature"
+// will allow you to configure the state of that feature.
+//
+// Please note that environmental variables can only be set to the boolean value.
+// Incorrect values will be ignored and logged.
+//
+// Features can also be set directly via the Set method.
+// In that case, these features take precedence over
+// features set via environmental variables.
+func newEnvVarFeatureGates(features map[Feature]FeatureSpec) *envVarFeatureGates {
+	known := map[Feature]FeatureSpec{}
+	for name, spec := range features {
+		known[name] = spec
+	}
+
+	fg := &envVarFeatureGates{
+		callSiteName: naming.GetNameFromCallsite(internalPackages...),
+		known:        known,
+	}
+	fg.enabledViaEnvVar.Store(map[Feature]bool{})
+	fg.enabledViaSetMethod = map[Feature]bool{}
+
+	return fg
+}
+
+// envVarFeatureGates implements Gates and allows for feature registration.
+type envVarFeatureGates struct {
+	// callSiteName holds the name of the file
+	// that created this instance
+	callSiteName string
+
+	// readEnvVarsOnce guards reading environmental variables
+	readEnvVarsOnce sync.Once
+
+	// known holds known feature gates
+	known map[Feature]FeatureSpec
+
+	// enabledViaEnvVar holds a map[Feature]bool
+	// with values explicitly set via env var
+	enabledViaEnvVar atomic.Value
+
+	// lockEnabledViaSetMethod protects enabledViaSetMethod
+	lockEnabledViaSetMethod sync.RWMutex
+
+	// enabledViaSetMethod holds values explicitly set
+	// via Set method, features stored in this map take
+	// precedence over features stored in enabledViaEnvVar
+	enabledViaSetMethod map[Feature]bool
+
+	// readEnvVars holds the boolean value which
+	// indicates whether readEnvVarsOnce has been called.
+	readEnvVars atomic.Bool
+}
+
+// Enabled returns true if the key is enabled. If the key is not known, this call will panic.
+func (f *envVarFeatureGates) Enabled(key Feature) bool {
+	if v, ok := f.wasFeatureEnabledViaSetMethod(key); ok {
+		// ensue that the state of all known features
+		// is loaded from environment variables
+		// on the first call to Enabled method.
+		if !f.hasAlreadyReadEnvVar() {
+			_ = f.getEnabledMapFromEnvVar()
+		}
+		return v
+	}
+	if v, ok := f.getEnabledMapFromEnvVar()[key]; ok {
+		return v
+	}
+	if v, ok := f.known[key]; ok {
+		return v.Default
+	}
+	panic(fmt.Errorf("feature %q is not registered in FeatureGates %q", key, f.callSiteName))
+}
+
+// Set sets the given feature to the given value.
+//
+// Features set via this method take precedence over
+// the features set via environment variables.
+func (f *envVarFeatureGates) Set(featureName Feature, featureValue bool) error {
+	feature, ok := f.known[featureName]
+	if !ok {
+		return fmt.Errorf("feature %q is not registered in FeatureGates %q", featureName, f.callSiteName)
+	}
+	if feature.LockToDefault && feature.Default != featureValue {
+		return fmt.Errorf("cannot set feature gate %q to %v, feature is locked to %v", featureName, featureValue, feature.Default)
+	}
+
+	f.lockEnabledViaSetMethod.Lock()
+	defer f.lockEnabledViaSetMethod.Unlock()
+	f.enabledViaSetMethod[featureName] = featureValue
+
+	return nil
+}
+
+// getEnabledMapFromEnvVar will fill the enabled map on the first call.
+// This is the only time a known feature can be set to a value
+// read from the corresponding environmental variable.
+func (f *envVarFeatureGates) getEnabledMapFromEnvVar() map[Feature]bool {
+	f.readEnvVarsOnce.Do(func() {
+		featureGatesState := map[Feature]bool{}
+		for feature, featureSpec := range f.known {
+			featureState, featureStateSet := os.LookupEnv(fmt.Sprintf("KUBE_FEATURE_%s", feature))
+			if !featureStateSet {
+				continue
+			}
+			boolVal, boolErr := strconv.ParseBool(featureState)
+			switch {
+			case boolErr != nil:
+				utilruntime.HandleError(fmt.Errorf("cannot set feature gate %q to %q, due to %v", feature, featureState, boolErr))
+			case featureSpec.LockToDefault:
+				if boolVal != featureSpec.Default {
+					utilruntime.HandleError(fmt.Errorf("cannot set feature gate %q to %q, feature is locked to %v", feature, featureState, featureSpec.Default))
+					break
+				}
+				featureGatesState[feature] = featureSpec.Default
+			default:
+				featureGatesState[feature] = boolVal
+			}
+		}
+		f.enabledViaEnvVar.Store(featureGatesState)
+		f.readEnvVars.Store(true)
+
+		for feature, featureSpec := range f.known {
+			if featureState, ok := featureGatesState[feature]; ok {
+				klog.V(1).InfoS("Feature gate updated state", "feature", feature, "enabled", featureState)
+				continue
+			}
+			klog.V(1).InfoS("Feature gate default state", "feature", feature, "enabled", featureSpec.Default)
+		}
+	})
+	return f.enabledViaEnvVar.Load().(map[Feature]bool)
+}
+
+func (f *envVarFeatureGates) wasFeatureEnabledViaSetMethod(key Feature) (bool, bool) {
+	f.lockEnabledViaSetMethod.RLock()
+	defer f.lockEnabledViaSetMethod.RUnlock()
+
+	value, found := f.enabledViaSetMethod[key]
+	return value, found
+}
+
+func (f *envVarFeatureGates) hasAlreadyReadEnvVar() bool {
+	return f.readEnvVars.Load()
+}

e2e/vendor/k8s.io/client-go/features/features.go

@@ -0,0 +1,143 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package features
+
+import (
+	"errors"
+	"sync/atomic"
+
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+)
+
+// NOTE: types Feature, FeatureSpec, prerelease (and its values)
+// were duplicated from the component-base repository
+//
+// for more information please refer to https://docs.google.com/document/d/1g9BGCRw-7ucUxO6OtCWbb3lfzUGA_uU9178wLdXAIfs
+
+const (
+	// Values for PreRelease.
+	Alpha = prerelease("ALPHA")
+	Beta  = prerelease("BETA")
+	GA    = prerelease("")
+
+	// Deprecated
+	Deprecated = prerelease("DEPRECATED")
+)
+
+type prerelease string
+
+type Feature string
+
+type FeatureSpec struct {
+	// Default is the default enablement state for the feature
+	Default bool
+	// LockToDefault indicates that the feature is locked to its default and cannot be changed
+	LockToDefault bool
+	// PreRelease indicates the maturity level of the feature
+	PreRelease prerelease
+}
+
+// Gates indicates whether a given feature is enabled or not.
+type Gates interface {
+	// Enabled returns true if the key is enabled.
+	Enabled(key Feature) bool
+}
+
+// Registry represents an external feature gates registry.
+type Registry interface {
+	// Add adds existing feature gates to the provided registry.
+	//
+	// As of today, this method is used by AddFeaturesToExistingFeatureGates and
+	// ReplaceFeatureGates to take control of the features exposed by this library.
+	Add(map[Feature]FeatureSpec) error
+}
+
+// FeatureGates returns the feature gates exposed by this library.
+//
+// By default, only the default features gates will be returned.
+// The default implementation allows controlling the features
+// via environmental variables.
+// For example, if you have a feature named "MyFeature"
+// setting an environmental variable "KUBE_FEATURE_MyFeature"
+// will allow you to configure the state of that feature.
+//
+// Please note that the actual set of the feature gates
+// might be overwritten by calling ReplaceFeatureGates method.
+func FeatureGates() Gates {
+	return featureGates.Load().(*featureGatesWrapper).Gates
+}
+
+// AddFeaturesToExistingFeatureGates adds the default feature gates to the provided registry.
+// Usually this function is combined with ReplaceFeatureGates to take control of the
+// features exposed by this library.
+func AddFeaturesToExistingFeatureGates(registry Registry) error {
+	return registry.Add(defaultKubernetesFeatureGates)
+}
+
+// ReplaceFeatureGates overwrites the default implementation of the feature gates
+// used by this library.
+//
+// Useful for binaries that would like to have full control of the features
+// exposed by this library, such as allowing consumers of a binary
+// to interact with the features via a command line flag.
+//
+// For example:
+//
+//	// first, register client-go's features to your registry.
+//	clientgofeaturegate.AddFeaturesToExistingFeatureGates(utilfeature.DefaultMutableFeatureGate)
+//	// then replace client-go's feature gates implementation with your implementation
+//	clientgofeaturegate.ReplaceFeatureGates(utilfeature.DefaultMutableFeatureGate)
+func ReplaceFeatureGates(newFeatureGates Gates) {
+	if replaceFeatureGatesWithWarningIndicator(newFeatureGates) {
+		utilruntime.HandleError(errors.New("the default feature gates implementation has already been used and now it's being overwritten. This might lead to unexpected behaviour. Check your initialization order"))
+	}
+}
+
+func replaceFeatureGatesWithWarningIndicator(newFeatureGates Gates) bool {
+	shouldProduceWarning := false
+
+	if defaultFeatureGates, ok := FeatureGates().(*envVarFeatureGates); ok {
+		if defaultFeatureGates.hasAlreadyReadEnvVar() {
+			shouldProduceWarning = true
+		}
+	}
+	wrappedFeatureGates := &featureGatesWrapper{newFeatureGates}
+	featureGates.Store(wrappedFeatureGates)
+
+	return shouldProduceWarning
+}
+
+func init() {
+	envVarGates := newEnvVarFeatureGates(defaultKubernetesFeatureGates)
+
+	wrappedFeatureGates := &featureGatesWrapper{envVarGates}
+	featureGates.Store(wrappedFeatureGates)
+}
+
+// featureGatesWrapper a thin wrapper to satisfy featureGates variable (atomic.Value).
+// That is, all calls to Store for a given Value must use values of the same concrete type.
+type featureGatesWrapper struct {
+	Gates
+}
+
+var (
+	// featureGates is a shared global FeatureGates.
+	//
+	// Top-level commands/options setup that needs to modify this feature gates
+	// should use AddFeaturesToExistingFeatureGates followed by ReplaceFeatureGates.
+	featureGates = &atomic.Value{}
+)

e2e/vendor/k8s.io/client-go/features/known_features.go

@@ -0,0 +1,77 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package features
+
+const (
+	// Every feature gate should add method here following this template:
+	//
+	// // owner: @username
+	// // alpha: v1.4
+	// MyFeature featuregate.Feature = "MyFeature"
+	//
+	// Feature gates should be listed in alphabetical, case-sensitive
+	// (upper before any lower case character) order. This reduces the risk
+	// of code conflicts because changes are more likely to be scattered
+	// across the file.
+
+	// owner: @benluddy
+	// kep: https://kep.k8s.io/4222
+	// alpha: 1.32
+	//
+	// If disabled, clients configured to accept "application/cbor" will instead accept
+	// "application/json" with the same relative preference, and clients configured to write
+	// "application/cbor" or "application/apply-patch+cbor" will instead write
+	// "application/json" or "application/apply-patch+yaml", respectively.
+	ClientsAllowCBOR Feature = "ClientsAllowCBOR"
+
+	// owner: @benluddy
+	// kep: https://kep.k8s.io/4222
+	// alpha: 1.32
+	//
+	// If enabled, and only if ClientsAllowCBOR is also enabled, the default request content
+	// type (if not explicitly configured) and the dynamic client's request content type both
+	// become "application/cbor" instead of "application/json". The default content type for
+	// apply patch requests becomes "application/apply-patch+cbor" instead of
+	// "application/apply-patch+yaml".
+	ClientsPreferCBOR Feature = "ClientsPreferCBOR"
+
+	// owner: @nilekhc
+	// alpha: v1.30
+	InformerResourceVersion Feature = "InformerResourceVersion"
+
+	// owner: @p0lyn0mial
+	// beta: v1.30
+	//
+	// Allow the client to get a stream of individual items instead of chunking from the server.
+	//
+	// NOTE:
+	//  The feature is disabled in Beta by default because
+	//  it will only be turned on for selected control plane component(s).
+	WatchListClient Feature = "WatchListClient"
+)
+
+// defaultKubernetesFeatureGates consists of all known Kubernetes-specific feature keys.
+//
+// To add a new feature, define a key for it above and add it here.
+// After registering with the binary, the features are, by default, controllable using environment variables.
+// For more details, please see envVarFeatureGates implementation.
+var defaultKubernetesFeatureGates = map[Feature]FeatureSpec{
+	ClientsAllowCBOR:        {Default: false, PreRelease: Alpha},
+	ClientsPreferCBOR:       {Default: false, PreRelease: Alpha},
+	InformerResourceVersion: {Default: false, PreRelease: Alpha},
+	WatchListClient:         {Default: false, PreRelease: Beta},
+}